Security Engineer Lead, Security Foundations

About the role

Security Foundations is Meta's first-line-of-defense technology organization, owning the controls that manage security risk across the company. We're looking for a Security Engineer Lead to scope, design, and champion security solutions company-wide across the domains we support. This is a breadth role. Each domain below has its own engineering leaders and managers — you will set technical direction across them rather than owning one. The hardest problems in this space does not sit inside a single domain. Agent identity and authorization, for example, spans identity and access, product authentication, AI security, and cloud simultaneously. Finding those problems and getting them solved once, coherently, is central to this role. The domains you'll influence: Identity and Access Management — the authorization layer every Meta system depends on, serving tens of billions of access checks per second Cryptography and Data Security — including Meta's post-quantum migration and Encryption at Rest Product Identity and Access — authentication for billions of end users AI Security — the controls protecting Meta's frontier AI products Cloud Security — securing Meta's footprint across public cloud and third-party compute providers, including identity, network egress, and posture management Asset Management — authoritative security risk classification for assets across the company Scope and complexity: -Security Foundations is a cross-functional organization of engineers, analysts, and product managers, partnering closely with hundreds of engineers elsewhere in the company. -The role spans a large set of technical domains: Meta's products and custom technology stack, commercial off-the-shelf software (e.g. Active Directory), and commercial IaaS/PaaS services. Familiarity with industry best practices and relevant regulatory frameworks — plus the ability to translate between those frameworks and deeply technical software engineers. What success looks like in the first year: -A defensible, company-wide view of the highest-risk items across these domains, with named owners and real threat models — not a list. -At least one shared platform or control adopted broadly enough to measurably change the company's risk posture. -Security tradeoffs represented credibly at the VP and C-level, with decisions made rather than deferred.

Responsibilities

Set technical direction for security solutions and platforms shared across the company, working through Security Engineering, Security Analyst, and Software Engineering teams. Determine the highest-risk items across these domains company-wide, then lead development of detailed threat models and solutions. Define how AI agents are identified, authorized, and audited across Meta's infrastructure — a space where neither existing industry practice nor our own human-centric models are sufficient. Navigate tradeoffs between security and friction or cost, so the company can keep moving fast securely. Drive solution design, including technical architecture, and lead implementation as needed. Build partnerships across security, infrastructure, corporate engineering, and legal — then use those partnerships to translate ambiguous business and regulatory requirements into well-articulated tradeoffs between "secure the company and our users" and "slow the company down.". Represent those tradeoffs credibly to senior leadership, including VPs and C-level executives (CTO, CISO), to drive decisions.